Computer is turning off

[JI]

My computer (Pent 4, Win XP) has begun to turn itself off without any
warning. Power is fine and it happens whether I'm on the net or not,
sometimes after 5 minutes, sometimes after 10, sometimes?

 

[DaveW]

The two basic scenarios are either something is overheating, or more likely,
your power supply unit is failing.

 

[Grant]

The two basic scenarios are either something is overheating, or more likely,
your power supply unit is failing.

Unless it is rebooting, not turning itself off, in which case it could also be a
virus, spyware, driver problem, hardware problem, etc...because windows by
default doesn't show the BSOD (blue screen of death) any more and just reboots.

If it is actually shutting off it could also be a lose PCI card.

 

[mentalalien]

Unless it is rebooting, not turning itself off, in which case it could
also be a
virus, spyware, driver problem, hardware problem, etc...because windows by
default doesn't show the BSOD (blue screen of death) any more and just
reboots.

If it is actually shutting off it could also be a lose PCI card.

If it's restarting it could also be a momentary PSU failure